TWI809487B - System and Method for Assessing Tube Pathway Status Using Fast Fourier Transform Spectrum Peak Ratio - Google Patents
System and Method for Assessing Tube Pathway Status Using Fast Fourier Transform Spectrum Peak Ratio Download PDFInfo
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Abstract
一種以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統,包含一擷取裝置及一評估裝置。該擷取裝置朝該廔管發射一無線電載波、接收由該無線電載波反射而成的信號並輸出為一傳輸信號。該評估裝置包括一通訊模組、一時頻域轉換模組、一比值運算模組及一機器學習模組。該評估裝置將該傳輸信號進行時頻域轉換,並取其中強度最大之頻率作為一基頻,運算該基頻的至少一諧波頻率區間所對應的強度值為至少一諧波強度值,運算其中一該諧波強度值與該基頻對應之強度值的比值或運算其中二該諧波強度值之比值,根據運算之比值輸出一評估結果。A system for estimating the channel state of the tube by the peak ratio of the fast Fourier transform spectrum, including an acquisition device and an evaluation device. The pick-up device transmits a radio carrier towards the tube, receives the signal reflected by the radio carrier and outputs it as a transmission signal. The evaluation device includes a communication module, a time-frequency domain conversion module, a ratio calculation module and a machine learning module. The evaluation device performs time-frequency domain conversion on the transmission signal, and takes the frequency with the largest intensity as a fundamental frequency, calculates the intensity value corresponding to at least one harmonic frequency interval of the fundamental frequency, and calculates A ratio of one of the harmonic intensity values to an intensity value corresponding to the fundamental frequency or a ratio of two of the harmonic intensity values is calculated, and an evaluation result is output according to the calculated ratio.
Description
本發明是有關於一種醫療評估系統與方法,特別是指一種以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統及方法。The present invention relates to a medical evaluation system and method, in particular to a system and method for evaluating the state of a tube channel by using the peak ratio of the fast Fourier transform spectrum.
慢性腎衰竭的病人必須先接受動靜脈廔管(arteriovenous fistula)的手術,才能進行洗腎治療,而由於動靜脈廔管的血流順暢度與洗腎效果密切相關,一旦廔管栓塞導致洗腎效果不佳或是無法洗腎,將造成病人須立即接受緊急處理甚或住院治療,因此,如何監控廔管通暢度以確保洗腎效果即為醫界重要研究目標。Patients with chronic renal failure must first undergo arteriovenous fistula surgery before undergoing dialysis treatment, and since the smoothness of blood flow in the arteriovenous fistula is closely related to the effect of dialysis, once the arteriovenous fistula is blocked and causes dialysis Poor effect or failure of dialysis will result in immediate emergency treatment or even hospitalization for the patient. Therefore, how to monitor the patency of the dialysis tube to ensure the effect of dialysis is an important research goal in the medical field.
目前醫院偵測廔管通路狀況,會使用Transonic公司之HD03血液透析監視儀,其使用方式是將兩根針頭***廔管適當處,以量測血流量並評估廔管通路功能健全度,其量測精確度高,但儀器價格昂貴,且每次使用之針頭、導管等耗材亦不便宜,因此,不適合作為常規之廔管通路監測方式。At present, the hospital will use Transonic HD03 hemodialysis monitor to detect the status of the vascular access. The method of use is to insert two needles into the appropriate part of the vascular access to measure the blood flow and evaluate the functional integrity of the vascular access. The measurement accuracy is high, but the instrument is expensive, and the consumables such as needles and catheters used each time are not cheap. Therefore, it is not suitable as a conventional monitoring method for tube access.
因此,本發明之目的,即在提供一種適用於常規監測廔管通路狀態的以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統。Therefore, the object of the present invention is to provide a system suitable for routinely monitoring the state of the tube path, which evaluates the state of the tube path by using the peak ratio of the fast Fourier transform spectrum.
於是,本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統,適用於量測評估一受試者的一廔管的通路狀態,包含一擷取裝置及一評估裝置。Therefore, the system of the present invention for evaluating the channel status of a tube using the peak ratio of the fast Fourier transform spectrum is suitable for measuring and evaluating the channel status of a tube of a subject, and includes an acquisition device and an evaluation device.
該擷取裝置包括一發射天線、一接收天線、一發射模組,及一接收模組,該發射模組經該發射天線朝該廔管發射一無線電載波,該接收模組經該接收天線接收由該無線電載波反射而成的一回波信號,該接收模組並將該回波信號輸出為一傳輸信號。The pick-up device includes a transmitting antenna, a receiving antenna, a transmitting module, and a receiving module. The transmitting module transmits a radio carrier wave towards the tube through the transmitting antenna, and the receiving module receives the signal through the receiving antenna. An echo signal reflected by the radio carrier, the receiving module outputs the echo signal as a transmission signal.
該評估裝置包括一通訊模組、一時頻域轉換模組、一比值運算模組,及一機器學習模組,該通訊模組信號連接該接收模組,接收該傳輸信號並輸出為一通訊信號,該時頻域轉換模組信號連接該通訊模組,接收該通訊信號並進行時頻域轉換以輸出一頻域資訊,該比值運算模組接收該頻域資訊並取該頻域資訊中強度最大之頻率作為一基頻,並運算該基頻的至少一諧波頻率區間所對應的強度值為至少一諧波強度值,運算其中一該諧波強度值與該基頻對應之強度值的比值或運算其中二該諧波強度值之比值,該機器學習模組根據運算之比值輸出一評估結果。The evaluation device includes a communication module, a time-frequency domain conversion module, a ratio calculation module, and a machine learning module. The communication module signal is connected to the receiving module, receives the transmission signal and outputs it as a communication signal , the time-frequency domain conversion module signal is connected to the communication module, receives the communication signal and performs time-frequency domain conversion to output a frequency domain information, the ratio operation module receives the frequency domain information and obtains the intensity of the frequency domain information The maximum frequency is taken as a fundamental frequency, and the intensity value corresponding to at least one harmonic frequency interval of the fundamental frequency is calculated at least one harmonic intensity value, and the intensity value corresponding to one of the harmonic intensity values and the fundamental frequency is calculated The ratio or the ratio of the two harmonic intensity values is calculated, and the machine learning module outputs an evaluation result according to the calculated ratio.
因此,本發明之目的,即在提供一種適用於常規監測廔管通路狀態的以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之方法。Therefore, the object of the present invention is to provide a method for evaluating the state of the tube path by using the peak ratio of the fast Fourier transform spectrum, which is suitable for routine monitoring of the tube path state.
於是,本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之方法,適用於量測評估一受試者的一廔管的通路狀態,包含以下步驟:Therefore, the method of the present invention for assessing the channel status of a tube using the ratio of the peak value of the fast Fourier transform spectrum is suitable for measuring and evaluating the channel status of a tube in a subject, and includes the following steps:
(A)朝該廔管發射一無線電載波,並接收由該無線電載波反射而成的一回波信號。(A) Transmitting a radio carrier toward the tube, and receiving an echo signal reflected by the radio carrier.
(B)將該回波信號輸出為一傳輸信號。(B) Outputting the echo signal as a transmission signal.
(C)將該傳輸信號輸出為一通訊信號,並將該通訊信號進行時頻域轉換以輸出一頻域資訊。(C) outputting the transmission signal as a communication signal, and performing time-frequency domain conversion on the communication signal to output a frequency domain information.
(D)取該頻域資訊中強度最大之頻率作為一基頻,並運算該基頻的至少一諧波頻率區間所對應的強度值為至少一諧波強度值,運算其中一該諧波強度值與該基頻對應之強度值的比值或運算其中二該諧波強度值之比值。(D) Take the frequency with the highest intensity in the frequency domain information as a fundamental frequency, and calculate the intensity value corresponding to at least one harmonic frequency interval of the fundamental frequency, and calculate one of the harmonic intensity values value and the intensity value corresponding to the fundamental frequency or calculate the ratio of two of the harmonic intensity values.
(E)根據運算之比值輸出一評估結果。(E) Outputting an evaluation result according to the calculated ratio.
本發明之功效在於:藉由發射該無線電載波並接收該回波信號,再搭配進行時頻域轉換取得該頻域資訊,及使用運算之比值供該機器學習模組進行評估,可以得到關於該廔管之血流量的預測結果,且本發明實施架構之價格實惠、操作方便、為非侵入性檢查,且無耗材產生,因此,十分適合作為醫院常規之廔管通路監測方式或是病患的居家護理監控。The effect of the present invention is: by transmitting the radio carrier wave and receiving the echo signal, and then performing time-frequency domain conversion to obtain the frequency domain information, and using the calculated ratio for the machine learning module to evaluate, it is possible to obtain information about the The prediction result of the blood flow of the tube, and the implementation structure of the present invention is affordable, easy to operate, non-invasive inspection, and no consumables are produced, so it is very suitable as a routine monitoring method of the tube access in the hospital or as a monitoring method for patients. Home care monitoring.
參閱圖1與圖2,本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統之一實施例,適用於量測評估一受試者的一廔管91(例如,動靜脈廔管(arteriovenous fistula))的通路狀態,包含一擷取裝置2及一評估裝置3。Referring to FIG. 1 and FIG. 2 , one embodiment of the system of the present invention for assessing the state of a tube access state with the ratio of the peak value of the fast Fourier transform spectrum is suitable for measuring and evaluating a tube 91 (for example, an arteriovenous tube ( Arteriovenous fistula)) includes an
該擷取裝置2適用於對應於該廔管91裝設於該受試者身上,並適用於靠近該受試者之皮膚92設置,例如,將該擷取裝置2貼靠於該受試者鄰近該動靜脈廔管91的靜脈端出口處之皮膚92上。該擷取裝置2包括一發射天線21、一接收天線22、一發射模組23,及一接收模組24,該發射模組23經該發射天線21朝該廔管91發射一無線電載波,該接收模組24經該接收天線22接收由該無線電載波反射而成的一回波信號,該接收模組24並將該回波信號輸出為一傳輸信號。The
該發射模組23具有一頻率可調方波產生電路231、一電連接該頻率可調方波產生電路231與該發射天線21的發射脈衝產生電路232,及一電連接該發射脈衝產生電路232的延遲脈衝產生電路233。The transmitting
該接收模組24具有一電連接該接收天線22的解調與濾波電路241、一電連接該解調與濾波電路241的類比數位轉換電路242,及一電連接該類比數位轉換電路242的傳輸電路243。該傳輸電路243可使用短距離無線傳輸技術實施,例如使用藍牙(Bluetooth)技術實施。The
該擷取裝置2之細節設置可見中華民國發明專利公告號I702938號「瘻管評估系統與方法」及發明專利申請號第109128981號「瘻管評估系統與方法」,因此,於本案中不再贅述。The details of the
該評估裝置3包括一通訊模組31、一時頻域轉換模組32、一比值運算模組33,及一機器學習模組34。其中,可使用一智慧型手機或平板等可攜式電子裝置實施該通訊模組31、該時頻域轉換模組32與該比值運算模組33,並使用一伺服器(server)實施該機器學習模組34,或亦可使用一伺服器直接實施該評估裝置3整體,於本實施例中,是以一智慧型手機搭配一伺服器進行說明,該手機可以使用預先安裝的APP(行動應用程式,mobile application)執行該通訊模組31、該時頻域轉換模組32與該比值運算模組33之功能運算。The
該通訊模組31與該傳輸電路243間可使用藍牙技術進行無線傳輸,該通訊模組31接收該傳輸信號並輸出為一通訊信號。Bluetooth technology can be used for wireless transmission between the
該時頻域轉換模組32信號連接該通訊模組31,接收該通訊信號並進行數位濾波及時頻域轉換以輸出一頻域資訊。該時頻域轉換模組32可將該通訊信號內含的該廔管91的位移資訊儲存於手機中,且可顯示於該手機之螢幕以供使用者觀看。其中,該時頻域轉換模組32之數位濾波功能可例如使用FIR(有限脈衝響應,Finite impulse response)濾波器實施,時頻域轉換功能則例如使用快速傅立葉轉換(Fast Fourier Transform,縮寫為FFT)實施。該時頻域轉換模組32可濾取一預定頻段以輸出為該頻域資訊,於本實施例中,是將該通訊信號濾取0.2Hz~10Hz之頻段進行時頻域轉換以輸出該頻域資訊。The time-frequency
該比值運算模組33接收該頻域資訊並取該頻域資訊中強度最大之頻率作為一基頻,並運算該基頻的至少一諧波頻率區間所對應的強度值為至少一諧波強度值,運算其中一該諧波強度值與該基頻對應之強度值的比值或運算其中二該諧波強度值之比值。例如,該比值運算模組33於該預定頻段(0.2Hz~10Hz)中取該基頻的n-1個諧波頻率區間所分別對應的強度值作為n-1個諧波強度值,並分別運算
作為n-1個諧波峰值比值,其中,n為一預定值,且為大於1的正整數,
為該基頻對應之強度值(即,第1個諧波頻率區間所對應之強度值),
為第n-1個諧波頻率區間所對應的諧波強度值,
為第n個諧波頻率區間所對應的諧波強度值。
The
該機器學習模組34預存至少一支援向量機341(support vector machine,縮寫為SVM),該支援向量機341根據該等n-1個諧波峰值比值輸出該評估結果。The
其中,該比值運算模組33與該機器學習模組34間(例如,該手機與該伺服器間)可以無線通訊網路技術(例如:GSM、Wi-Fi、藍牙技術等)進行訊號傳輸。該支援向量機341需先使用例如K折交叉驗證(K-fold Cross-Validation)方式進行訓練,以得到對應於一血流參數的預測模型。Wherein, the signal transmission between the
參閱圖1、圖2、圖6及圖7,實際應用時,可搭配本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之方法之一實施例進行測試,該以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之方法包含以下步驟:Referring to Fig. 1, Fig. 2, Fig. 6 and Fig. 7, during actual application, one embodiment of the method for evaluating the channel status of the channel with the fast Fourier transform spectrum peak ratio of the present invention can be used for testing. The method of assessing the state of the pipeline access includes the following steps:
步驟51:朝該廔管91發射一無線電載波,並接收由該無線電載波反射而成的一回波信號。Step 51: Transmit a radio carrier toward the
步驟52:將該回波信號輸出為一傳輸信號。Step 52: Output the echo signal as a transmission signal.
步驟53:將該傳輸信號輸出為一通訊信號,並將該通訊信號進行時頻域轉換以輸出一頻域資訊。Step 53: Output the transmission signal as a communication signal, and perform time-frequency domain conversion on the communication signal to output a frequency domain information.
其中,本實施例中,以每秒64次的頻率取樣1分鐘的該通訊信號,並先將該通訊信號進行數位濾波以濾取該預定頻段再進行處理,例如,可濾取0.2Hz~10Hz之頻段進行時頻域轉換以輸出該頻域資訊。請參照圖3~圖6,該通訊信號為時域訊號,其中一波形約如圖3或圖4所示,該通訊信號經由數位濾波與時頻域轉換後,則會形成如圖5或圖6所示之頻譜圖。Wherein, in this embodiment, the communication signal of 1 minute is sampled at a frequency of 64 times per second, and the communication signal is digitally filtered to filter out the predetermined frequency band before processing, for example, 0.2Hz~10Hz can be filtered out Time-frequency domain conversion is performed on the frequency band to output the frequency domain information. Please refer to Figure 3~Figure 6, the communication signal is a time-domain signal, and one of the waveforms is shown in Figure 3 or Figure 4. After the communication signal is digitally filtered and time-frequency domain converted, it will be formed as Figure 5 or Figure 4. The spectrum diagram shown in 6.
參閱圖1、圖2、圖6及圖7,步驟54:取該頻域資訊中強度最大之頻率作為一基頻,並運算該基頻的至少一諧波頻率區間所對應的強度值為至少一諧波強度值,運算其中一該諧波強度值與該基頻對應之強度值的比值或運算其中二該諧波強度值之比值。Referring to Fig. 1, Fig. 2, Fig. 6 and Fig. 7, step 54: take the frequency with the largest intensity in the frequency domain information as a fundamental frequency, and calculate the intensity value corresponding to at least one harmonic frequency interval of the fundamental frequency at least A harmonic intensity value, calculating the ratio of one of the harmonic intensity values to the intensity value corresponding to the fundamental frequency or calculating the ratio of two of the harmonic intensity values.
其中,取該基頻的n-1個諧波頻率區間所分別對應的強度值作為n-1個諧波強度值,並分別運算 作為n-1個諧波峰值比值,n為一預定值,且為大於1的正整數, 為該基頻對應之強度值, 為第n-1個諧波頻率區間所對應的諧波強度值, 為第n個諧波頻率區間所對應的諧波強度值。值得一提的是,亦可僅運算部分的諧波峰值比值,例如,僅運算 ,或僅運算 ,或僅運算 等,或亦可使用 作為n-1個諧波峰值比值,不以此為限。 Among them, take the intensity values corresponding to the n-1 harmonic frequency intervals of the fundamental frequency as the n-1 harmonic intensity values, and calculate As the n-1 harmonic peak ratio, n is a predetermined value, and is a positive integer greater than 1, is the intensity value corresponding to the fundamental frequency, is the harmonic intensity value corresponding to the n-1th harmonic frequency interval, is the harmonic intensity value corresponding to the nth harmonic frequency interval. It is worth mentioning that it is also possible to calculate only part of the harmonic peak ratio, for example, only calculate , or just the operation , or just the operation etc., or you can also use As the ratio of n-1 harmonic peak values, it is not limited thereto.
例如,以n=2說明,取該基頻的一個諧波頻率區間(例如,該基頻之二次諧波與鄰近區間,或亦可取三次諧波與鄰近區間、或四次諧波與鄰近區間、或五次諧波與鄰近區間、或六次諧波與鄰近區間…等)所對應的強度值作為該諧波強度值,並運算 作為該諧波峰值比值, 為該基頻對應之強度值, 為該基頻的第2個諧波頻率區間(即二次諧波與鄰近區間)所對應的諧波強度值。 For example, with n=2, take a harmonic frequency interval of the fundamental frequency (for example, the second harmonic and adjacent intervals of the fundamental frequency, or the third harmonic and adjacent intervals, or the fourth harmonic and adjacent intervals) interval, or the fifth harmonic and adjacent intervals, or the sixth harmonic and adjacent intervals, etc.) as the harmonic intensity value, and calculate As the harmonic peak ratio, is the intensity value corresponding to the fundamental frequency, is the harmonic intensity value corresponding to the second harmonic frequency interval of the fundamental frequency (that is, the second harmonic and adjacent intervals).
以n=6說明,取該基頻的5個諧波頻率區間(例如,取該基頻之二次諧波與鄰近區間、三次諧波與鄰近區間、四次諧波與鄰近區間、五次諧波與鄰近區間、六次諧波與鄰近區間)所分別對應的強度值作為5個諧波強度值,並分別運算 、 、 、 、 作為5個諧波峰值比值, 為該基頻對應之強度值, 、 、 、 、 分別為第2~6個諧波頻率區間(即二次諧波與鄰近區間、三次諧波與鄰近區間、四次諧波與鄰近區間、五次諧波與鄰近區間、六次諧波與鄰近區間)所對應的諧波強度值。 With n=6, take the 5 harmonic frequency intervals of the fundamental frequency (for example, take the second harmonic of the fundamental frequency and the adjacent interval, the third harmonic and the adjacent interval, the fourth harmonic and the adjacent interval, the fifth The intensity values corresponding to the harmonics and adjacent intervals, the sixth harmonic and adjacent intervals) are taken as the five harmonic intensity values, and are calculated separately , , , , As the ratio of the peak values of the 5 harmonics, is the intensity value corresponding to the fundamental frequency, , , , , They are the 2nd to 6th harmonic frequency intervals (that is, the second harmonic and the adjacent interval, the third harmonic and the adjacent interval, the fourth harmonic and the adjacent interval, the fifth harmonic and the adjacent interval, the sixth harmonic and the adjacent interval interval) corresponding to the harmonic intensity value.
其中,可參照圖6,於本實施例中,由於該預定頻段為0.2Hz ~10Hz,而強度最大之頻率(該基頻)一般落在1Hz~2Hz之間,因此,n值一般定為小於10的正整數(或是定為小於8的正整數),於本實施例中,該比值運算模組33是以n=6進行運算。Wherein, with reference to Fig. 6, in the present embodiment, since the predetermined frequency band is 0.2Hz ~ 10Hz, and the frequency with the greatest intensity (the fundamental frequency) generally falls between 1Hz ~ 2Hz, therefore, the value of n is generally defined as less than A positive integer of 10 (or a positive integer smaller than 8), in this embodiment, the
其中,該等諧波強度值 ~ 之取法為,先取該基頻的2~n倍值分別作為n-1個參考諧波頻率,並以每一參考諧波頻率與其上下一預定區間作為該諧波頻率區間,取該諧波頻率區間中的強度最大值作為對應的該諧波強度值。例如,以取第2個諧波強度值說明,假設該基頻之頻率為1.3Hz,該預定區間為0.05Hz,則先取該基頻2倍值2.6Hz作為參考諧波頻率,再以2.6Hz與其上下該預定區間2.55Hz~2.65Hz作為該諧波頻率區間,再以2.55Hz~2.65Hz區間中的強度最大值作為對應的該諧波強度值。 Among them, such harmonic intensity values ~ The method is to take 2~n times of the fundamental frequency as n-1 reference harmonic frequencies respectively, and take each reference harmonic frequency and its upper and lower predetermined intervals as the harmonic frequency interval, and take the harmonic frequency The intensity maximum value in the interval is taken as the corresponding harmonic intensity value. For example, to take the second harmonic intensity value to illustrate, assuming that the frequency of the fundamental frequency is 1.3Hz and the predetermined interval is 0.05Hz, first take the value 2.6Hz which is twice the fundamental frequency as the reference harmonic frequency, and then use 2.6Hz The predetermined interval 2.55Hz-2.65Hz above and below is used as the harmonic frequency interval, and then the maximum intensity value in the interval 2.55Hz-2.65Hz is used as the corresponding harmonic intensity value.
步驟55:根據運算之比值輸出一評估結果。Step 55: Output an evaluation result according to the calculated ratio.
其中,該支援向量機341根據該等n-1個諧波峰值比值輸出該評估結果,該評估結果為該支援向量機341的預測類別,一般為1或0之輸出。Wherein, the
於實際應用時,該機器學習模組34中可以內建一或多個支援向量機341,每一支援向量機341對應不同的該血流參數,例如,該機器學習模組34中可以只內建1個對應於600毫升/分鐘(ml/min)之流量的支援向量機341,或是可內建有7個支援向量機341,該等支援向量機341分別對應於500、600、650、750、900、1200、3500 ml/min之流量,或是可內建上述7個支援向量機341,但於販售時根據客戶的選擇而僅開放其中一個或多個支援向量機341的使用權限供客戶使用。In actual application, one or more
當要進行評估時,先以步驟51~步驟54量測該受試者以獲得該等諧波峰值比值
,接著,將該等諧波峰值比值
輸入所選擇(或具有使用權限)的該支援向量機341。例如,選擇對應於600 ml/min流量的該支援向量機341時,若該支援向量機341輸出之該評估結果為1,則表示該受試者之廔管91的預測血流量大於600 ml/min,若輸出之該評估結果為0,則表示該受試者之廔管91的預測血流量低於等於600 ml/min。醫護人員可根據需求而選擇對應合適該血流參數的該支援向量機341,並根據輸出的該評估結果判斷是否需要進行進一步的檢查。
When evaluating, first measure the subject in
該以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之方法,還包含下列訓練(training)步驟:The method for evaluating the channel state of the tube by the ratio of the peak value of the fast Fourier transform spectrum also includes the following training steps:
步驟61:收集至少一訓練資料組,每一訓練資料組對應不同之一血流參數且具有複數筆分別對應複數預試者的訓練資料,每一筆訓練資料具有一判定類別及n-1個諧波峰值比值。Step 61: Collect at least one training data group, each training data group corresponds to a different blood flow parameter and has a plurality of training data corresponding to a plurality of pre-testers, each training data has a judgment category and n-1 harmonics Peak-to-peak ratio.
其中,需先根據需求定義該至少一血流參數,並根據所定義的該血流參數收集該訓練資料組。例如,當定義單一個該血流參數(例如,600 ml/min)時,則須收集一組對應600 ml/min血流量的該訓練資料組,當定義多個該血流參數(例如,600 ml/min與750 ml/min)時,則須收集一組對應600 ml/min血流量的該訓練資料組、與一組對應750 ml/min血流量的該訓練資料組。以此類推,不再贅述。Wherein, the at least one blood flow parameter needs to be defined according to requirements, and the training data set is collected according to the defined blood flow parameter. For example, when defining a single blood flow parameter (for example, 600 ml/min), then a set of training data sets corresponding to a blood flow of 600 ml/min must be collected; when multiple blood flow parameters (for example, 600 ml/min) are defined ml/min and 750 ml/min), it is necessary to collect a set of training data corresponding to the blood flow of 600 ml/min, and a set of training data corresponding to the blood flow of 750 ml/min. And so on, no more details.
以一組對應600 ml/min血流量的該訓練資料組作為說明,該訓練資料組具有複數筆分別對應複數預試者(於本實施例中,為45位)的訓練資料,每一筆訓練資料具有該判定類別及n-1個諧波峰值比值,該判定類別之資料為0或1,0表示低於等於該血流參數,1表示高於該血流參數。該等n-1個諧波峰值比值是使用步驟51~54對該等預試者進行量測所得。該判定類別是根據該血流參數與使用血流流量黃金標準儀器(例如,Transonic公司之HD03血液透析監視儀)量測該等預試者之血流量而得。例如,當其中一筆訓練資料為[0,
]時,表示該筆訓練資料所對應的該預試者所量測的血流量低於等於600 ml/min,而
為該預試者經步驟51~54量測及運算所得之諧波峰值比值。
Take the training data group corresponding to a blood flow of 600 ml/min as an illustration. This training data group has a plurality of training data corresponding to a plurality of pre-testers (in this embodiment, 45 persons). Each training data With the judgment category and n-1 harmonic peak ratios, the data of the judgment category is 0 or 1, 0 means lower than or equal to the blood flow parameter, 1 means higher than the blood flow parameter. The n-1 harmonic peak ratios are obtained by measuring the pre-testers using steps 51-54. The determination category is obtained based on the blood flow parameters and the blood flow of the pre-examination subjects measured with a blood flow gold standard instrument (for example, Transonic's HD03 hemodialysis monitor). For example, when one of the training data is [0, ], it means that the blood flow measured by the test subject corresponding to the training data is lower than or equal to 600 ml/min, while It is the harmonic peak ratio obtained by the pre-tester through the measurement and calculation of
步驟62:根據該至少一訓練資料組訓練至少一支援向量機341,每一支援向量機341對應不同的該血流參數。Step 62: Train at least one
其中,該支援向量機341可使用例如K折交叉驗證(K-fold Cross-Validation)方式進行訓練,以得到對應於該血流參數的預測模型。於本實施例中,設定K值為10,即,將該訓練資料組中的多筆訓練資料分為10組,每組可均分到相同數量之訓練資料,或分配不同數量之訓練資料,以其中任意9組作為訓練組,剩餘1組作為測試組,完成第1次訓練後,由訓練組中挑出一組未曾作為測試組的資料作為下一輪的測試組,其餘9組作為下一輪的訓練組,接著進行下一輪的訓練,如此直到每一組資料都作過測試組,即完成該支援向量機341之訓練。Wherein, the
本發明之原理說明如下:Principle of the present invention is described as follows:
該擷取裝置2適用於發射該無線電載波穿透皮膚92後從該廔管91表面反射,該廔管91因血壓脈動而產生週期位移,此位移所造成的都普勒效應(Doppler effect)會改變該無線電載波的頻率並形成該回波信號,該回波信號的特徵與廔管91通路的狹窄有高度相關性,其原因可基於流體力學理論進行說明,當血液通過廔管91管徑狹窄處,因廔管91狹窄處的血流速度會增加並產生亂流,因此,在廔管91靜脈端出口處偵測到的訊號會包含震動弦波成份,造成訊號非線性失真現象。參閱圖3~圖6,圖3及圖5為健康者之其中一血壓波形的圖片及將所量測的訊號進行時頻域轉換等處理後輸出的該頻域資訊,圖4及圖6則為被判斷為該廔管91狹窄之病患的其中一血壓波形的圖片,及將所量測的訊號進行時頻域轉換等處理後輸出的該頻域資訊。將兩組圖片進行比較,可以看出兩組圖片在波形與頻譜強度分布上皆具有差異(圖5及圖6中之虛線為波形43、44的端點近似曲線)。並且,經由將兩組該頻域資訊之諧波峰值比值進行獨立樣本T檢定(independent T test),於血流參數為600 ml/min時,於
的T檢定得到之P值(P-value)為0.008,於血流參數為650 ml/min時,於
的T檢定得到之P值為0.035,於血流參數為750 ml/min時,於
的T檢定得到之P值為0.041,上述之P值皆小於0.05,足證兩者(正常與廔管91狹窄)之諧波峰值比值間具有顯著差異。
The pick-up
請參下表1~3,為使用本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統及方法之實施例對45個受試者進行血流評估的結果,表1~3分別是以血流參數為600、650、750 ml/min進行評估,所採用之基準真相(Ground Truth)為,使用Transonic公司之HD03血液透析監視儀量測該受試者的血流量,低於等於對應之該血流參數,則列為0,高於對應之該血流參數,則列為1。
由表1~3可見,本實施例在血流參數為600、650、750 ml/min時,特異度(Specificity)皆高達100%,而靈敏度(Sensitivity)也分別高達90.9%、93.8%、95.2%,足證本實施例的血流評估確實具有極佳的準確度。It can be seen from Tables 1 to 3 that in this example, when the blood flow parameters are 600, 650, and 750 ml/min, the specificity (Specificity) is as high as 100%, and the sensitivity (Sensitivity) is also as high as 90.9%, 93.8%, and 95.2% respectively. %, which fully proves that the blood flow assessment in this embodiment does have excellent accuracy.
請參閱圖9及下表4,曲線45為本實施例根據血流參數500、600、650、750、900、1200、1800、3500 ml/min之特異度與靈敏度所繪製的接收者操作特徵曲線(receiver operating characteristic curve,或ROC曲線),其ROC曲線下方的面積(Area under the Curve of ROC,或稱AUC)為0.997,其值趨近於1,足證本實施例之預測正確率極高。
參閱圖1及圖2,經由以上的說明,本實施例的功效如下:Referring to Fig. 1 and Fig. 2, through the above description, the effect of the present embodiment is as follows:
一、藉由發射該無線電載波並接收該回波信號,再搭配進行時頻域轉換取得該頻域資訊,及使用該諧波頻率區間與該基頻對應之強度值的比值供該機器學習模組34進行評估,可以得到關於該廔管91之血流量之預測結果。1. By transmitting the radio carrier and receiving the echo signal, and then performing time-frequency domain conversion to obtain the frequency domain information, and using the ratio of the harmonic frequency interval to the intensity value corresponding to the fundamental frequency for the machine learning model The
並且,由於本實施例是使用無線電載波方式進行量測,其實施架構之價格遠較Transonic公司之HD03血液透析監視儀實惠,操作也更為方便,且並非侵入性檢查、無耗材產生,因此,十分適合作為醫院常規之廔管91通路評估方式或是病患的居家護理監控,再由醫護人員根據所預測的廔管91之血流量,初步評估病患之廔管91是否可能異常,或是否需要再使用Transonic公司之HD03血液透析監視儀(或超音波、血管攝影等方式)進行更精確的檢查。藉此,可方便醫護人員隨時量測病患之廔管91的血流量,提高病患在未發生栓塞前能早期發現廔管91是否狹窄化的機率,以及早安***密診斷,評估是否需進行動靜脈廔管91整型術。故本實施例能供醫護人員評估掌控洗腎效果,有效降低病患的再入院率、減少醫療支出及提高生活品質。Moreover, since this embodiment uses the radio carrier method for measurement, the price of its implementation structure is far more affordable than Transonic’s HD03 hemodialysis monitor, the operation is more convenient, and it is not an invasive inspection and no consumables are produced. Therefore, It is very suitable as a routine evaluation method of the
再者,根據本實施例之量測驗證結果,本實施例在血流參數為600、650、750 ml/min時,特異度皆高達100%,而靈敏度也分別高達90.9%、93.8%、95.2%,在血流參數為900、1200 ml/min時,靈敏度皆高達100%,在血流參數為1800、3500 ml/min時,特異度與靈敏度皆高達100%,AUC之值則高達0.997,足證本實施例確實具有極佳的預測準確度。Furthermore, according to the measurement verification results of this example, when the blood flow parameters of this example are 600, 650, and 750 ml/min, the specificity is as high as 100%, and the sensitivity is as high as 90.9%, 93.8%, and 95.2% respectively. %, when the blood flow parameters are 900 and 1200 ml/min, the sensitivity is as high as 100%, when the blood flow parameters are 1800 and 3500 ml/min, the specificity and sensitivity are both as high as 100%, and the AUC value is as high as 0.997, It proves that this embodiment does have excellent prediction accuracy.
綜上所述,本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統及方法,確實能達成本發明的目的。To sum up, the system and method of the present invention for assessing the channel state of the tube by using the peak ratio of the fast Fourier transform spectrum can indeed achieve the purpose of the present invention.
惟以上所述者,僅為本發明之實施例而已,當不能以此限定本發明實施之範圍,凡是依本發明申請專利範圍及專利說明書內容所作之簡單的等效變化與修飾,皆仍屬本發明專利涵蓋之範圍內。But what is described above is only an embodiment of the present invention, and should not limit the scope of the present invention. All simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the patent specification are still within the scope of the present invention. Within the scope covered by the patent of the present invention.
2:擷取裝置
21:發射天線
22:接收天線
23:發射模組
231:頻率可調方波產生電路
232:發射脈衝產生電路
233:延遲脈衝產生電路
24:接收模組
241:解調與濾波電路
242:類比數位轉換電路
243:傳輸電路
3:評估裝置
31:通訊模組
32:時頻域轉換模組
33:比值運算模組
34:機器學習模組
341:支援向量機
41~44:波形
45:曲線
51~55:步驟
61~62:步驟
91:廔管
92:皮膚
~
:第1~6個諧波頻率區間的諧波強度值
2: Capture device 21: Transmitting antenna 22: Receiving antenna 23: Transmitting module 231: Frequency adjustable square wave generating circuit 232: Transmitting pulse generating circuit 233: Delayed pulse generating circuit 24: Receiving module 241: Demodulation and filtering Circuit 242: Analog-digital conversion circuit 243: Transmission circuit 3: Evaluation device 31: Communication module 32: Time-frequency domain conversion module 33: Ratio calculation module 34: Machine learning module 341:
本發明之其他的特徵及功效,將於參照圖式的實施方式中清楚地呈現,其中: 圖1是本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之系統的一實施例應用於量測一廔管的示意圖; 圖2是該實施例的一方塊示意圖; 圖3是該實施例所量測的一健康者之血壓波形圖; 圖4是該實施例所量測的一被判斷為廔管狹窄之病患的血壓波形圖; 圖5是該實施例所產生的一相關於健康者的頻域資訊; 圖6是該實施例所產生的一相關於廔管狹窄之病患的頻域資訊; 圖7、8是本發明以快速傅立葉轉換頻譜峰值比例評估廔管通路狀態之方法的一實施例的二流程圖;及 圖9為該實施例的一接收者操作特徵曲線圖。 Other features and effects of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a schematic diagram of an embodiment of the system for evaluating the channel state of a tube by the peak ratio of the fast Fourier transform spectrum of the present invention applied to the measurement of a tube; Fig. 2 is a schematic block diagram of this embodiment; Fig. 3 is the waveform diagram of blood pressure of a healthy person measured in this embodiment; Fig. 4 is a blood pressure wave diagram of a patient who is judged to be stenosis of the canal stenosis measured in this embodiment; Fig. 5 is the frequency domain information related to a healthy person generated by this embodiment; Fig. 6 is the frequency domain information of a patient related to the stenosis of the canal stenosis generated by this embodiment; 7 and 8 are two flow charts of an embodiment of the method for evaluating the channel state of the tube with the peak ratio of the fast Fourier transform spectrum of the present invention; and FIG. 9 is a receiver operating characteristic graph of the embodiment.
2:擷取裝置 2: Capture device
21:發射天線 21: Transmitting antenna
22:接收天線 22: Receiving antenna
23:發射模組 23: launch module
231:頻率可調方波產生電路 231: Frequency adjustable square wave generating circuit
232:發射脈衝產生電路 232: Transmitting pulse generating circuit
233:延遲脈衝產生電路 233: Delayed pulse generating circuit
24:接收模組 24: Receiving module
241:解調與濾波電路 241: Demodulation and filter circuit
242:類比數位轉換電路 242: Analog to digital conversion circuit
243:傳輸電路 243: transmission circuit
3:評估裝置 3: Evaluation device
31:通訊模組 31: Communication module
32:時頻域轉換模組 32: Time-frequency domain conversion module
33:比值運算模組 33: Ratio operation module
34:機器學習模組 34:Machine Learning Module
341:支援向量機 341:Support vector machine
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